Name: Armillaria tabescens (Scop.) Emel
Most Confident Observations:
Copyright © 2011 Stephen (Ιερονυμοσ)
Copyright © 2017 John (John FungiFlora)
Copyright © 2018 walt sturgeon (Mycowalt)
Version: 26
Previous Version 


Domain: Eukarya

Kingdom: Fungi

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Agaricales

Family: Physalacriaceae

Genus: Armillaria

Brief Description: [See More | Edit]

Cap: 1-6 cm across at maturity; convex at first, becoming broadly convex or flat in age; dry; tan to tawny brown or cinnamon brown—or sometimes yellow to yellowish; when young covered with darker brown scales, but at maturity the scales are often concentrated near the center and vaguely radially arranged; the margin often becoming slightly lined.

Gills: Running down the stem or nearly so; close or nearly distant; whitish with pinkish hints; sometimes bruising or discoloring slightly pinkish to brownish.

Stem: 5-20 cm long; 0.5-1.5 cm. thick; tapering to base; bald and pale near apex, darker and nearly hairy below; without a ring.

Flesh: Whitish to watery tan; sometimes insubstantial in stem.

Odor and Taste: Taste mild or bitter; odor sweet.

Chemical Reactions: KOH negative on cap surface.

Spore Print: White.

Microscopic Features: Spores 8-10 × 5-7 µ; smooth; more or less ellipsoid; inamyloid; with a prominent apiculus. Pileipellis a cutis of brown, frequently septate elements 7.5-15 µ wide, occasionally arranged in upright fascicles. Cheilocystidia clavate to subclavate or subsaccate; to about 40 × 10 µ; thin-walled; hyaline. Pleurocystidia absent. Basidia 2- and 4-sterigmate; not basally clamped.

Descriptions: [Create]


Add Comment
Deprecate the Name pages!
By: Oluna & Adolf Ceska (
2020-05-26 14:55:56 CDT (-0400)

Replace them with the following advice:
In spelling the fungal names and when citing the name authorities, follow the Index/Species Fungorum, as close as possible.

By: Erlon Bailey (Herbert Baker)
2020-05-26 10:09:56 CDT (-0400)

None of the other accessible databases have two competing names as both preferred. e.g., Index Fungorum, Mycobank, Inaturalist etc..

MO is not following established guidelines and is only causing more confusion.

By: Joseph D. Cohen (Joe Cohen)
2020-05-25 11:36:39 CDT (-0400)

To end the deprecation war,
- I am approving Armillaria tabescens, leaving Desarmillaria tabescens as an MO Approved Name;
- Locking A. tabescens.

By: Alan Rockefeller (Alan Rockefeller)
2020-05-23 14:18:36 CDT (-0400)

Desarmillaria was an unnecessary split and shouldn’t be used.

There have been plenty of “consensus” names that haven’t stood the test of time
By: Django Grootmyers (Heelsplitter)
2020-05-20 19:02:59 CDT (-0400)


Consensus here is also an aggregate of opinions, and relatively few to be honest, since the decision to split or not split Armillaria was subjective since Armillaria would remain monophyletic either way. There also isn’t some ICN rule that states that you have to just accept “consensus” names.

If your “one taxon, one name” comment is in reference to the ICN’s “one fungus, one name” (1F1N) policy, that relates to the past practice of having separate names for anamorphs and teleomorphs.

It seems that Armillaria affinis may be basal to the rest of Armillaria including the Desarmillariella clade based on the recent Vargas (2019) analysis, but the support for this is pretty weak. Still, a larger sample size might make the logic for splitting Armillaria even flimsier, since it rests somewhat on the assumption that Desarmillariella is the basal clade.

Walt: No, it doesn’t. A. tabescens is still more closely related to the rest of the Armillaria species other than to things like A. ectypa whether you call it Desarmillariella or Armillaria.

Re: One taxon, one name
By: Oluna & Adolf Ceska (
2020-05-20 19:02:17 CDT (-0400)

There are many taxa, but none of them is Armillaria tabescens.

DNA evidence
By: walt sturgeon (Mycowalt)
2020-05-20 18:45:25 CDT (-0400)

Does it show conclusively that this species is not closely aligned with other Armillaria species?

By: Django Grootmyers (Heelsplitter)
2020-05-20 17:19:30 CDT (-0400)

Still a valid name. Whether the split should be accepted or not is a matter of opinion. The 2 names should remain accepted

I would go with Desarmillaria tabescens (Scop.) R.A. Koch & Aime
By: Oluna & Adolf Ceska (
2020-05-20 14:08:47 CDT (-0400)

It has not been here before!

Deprecate the deprecation!
By: Oluna & Adolf Ceska (
2020-05-20 11:55:14 CDT (-0400)

If you want to follow the spirit of International Code of Nomenclature, deprecate the deprecation!

By: Alan Rockefeller (Alan Rockefeller)
2018-08-24 21:39:32 CDT (-0400)

Unnecessary splits should be ignored.

MyCoPortal has a great solution
By: Oluna & Adolf Ceska (
2018-02-01 19:37:58 CST (-0500)

For their searches, MyCoPortal has a great solution. It is the Taxonomic Thesaurus that gives you search results not only for the name you entered, but also for the synonyms of the name you searched for. MO should make a deal with MyCoPortal and build the Taxonomic Thesaurus into our MO system. I can imagine that to build up such Thesaurus and beef it up with names requires unique encyclopedic knowledge of the nomenclature of fungi. Would it be possible to get it from the MyCoPortal as a sealed unit and let it on them to make the updates?

By: Jacob Kalichman (Pulk)
2018-02-01 19:31:48 CST (-0500)

Requiring everyone to agree that a name shouldn’t be used is far too strict. There are always going to be idiots clinging to patently wrong old names for terrible reasons.

The reasons for Armillaria tabescens are good, but the reasons for Desarmillaria tabescens are better, and letting multiple names float around is confusing. From my post on FB: “That’s how the genera are going to be treated in future literature. When you read a new paper next year you don’t want to have to figure out if the cool weird attribute it’s describing is about the hobby Armillaria or the mycologists’ Armillaria. And when some new Desarmillaria species is described without a corresponding Armillaria combination, you’re going to have to accept the genus anyway.” I’m sympathetic to questionable cases having multiple names accepted (Lepista nuda and Clitocybe nuda), but I’m not convinced there’s that much ambiguity here.

Anyway, there are much more egregious errors in other parts of MO so this is the last time I’ll deprecate “A. tabescens” (…for now…)

By: Alan Rockefeller (Alan Rockefeller)
2018-02-01 19:09:21 CST (-0500)

There is nothing wrong with this name so it should not be deprecated. Only names that everyone agrees should not be used should be deprecated. There are lots of examples of taxa with multiple valid names, and which one to use is a matter of personal preference and taxonomic philosophy.

Gentlemen, Stop it!
By: Oluna & Adolf Ceska (
2018-02-01 18:49:19 CST (-0500)

This honey mushroom does not really care, how it is called. Follow the Interantional Code of Nomenclature of … and forget deprecation!

By: Jacob Kalichman (Pulk)
2018-02-01 17:14:40 CST (-0500)

It wasn’t a mistake; they used it multiple times, obviously consciously. It’s not a fluke; these are different authors, a year later from the 2017 paper that established it as a genus.

By: Alan Rockefeller (Alan Rockefeller)
2018-02-01 16:52:50 CST (-0500)

Just because the new Armillaria paper made the mistake of using Desarmillaria doesn’t mean that we need to make the same error on MO.

By: Jacob Kalichman (Pulk)
2018-02-01 15:55:32 CST (-0500)

Agreed, but the split was made and other Armillariologists have adopted the name. Because one synonym should be chosen as preferred and this is the direction taxonomists have chosen, MO should use Desarmillaria. I would love to see a publication explicitly rejecting Desarmillaria, and therefore reason to change it back on MO.

By: Alan Rockefeller (Alan Rockefeller)
2018-02-01 14:36:02 CST (-0500)

Desarmillaria was an unnecessary split.

Deprecate the deprecation! Consensus is nonsensus
By: Oluna & Adolf Ceska (
2018-02-01 12:34:36 CST (-0500)
By: Jacob Kalichman (Pulk)
2018-02-01 10:11:17 CST (-0500)

A new Armillaria paper with entirely different authors uses the name without qualification; this makes it the current Armillariologist “consensus”.

By: Alan Rockefeller (Alan Rockefeller)
2017-07-11 19:36:31 CDT (-0400)

There was no good reason to split Armillaria.

A. tabescens or A. socialis?
By: Dmitriy Bochkov (convallaria)
2012-08-01 02:07:24 CDT (-0400)

There is a paper, External Link , which concludes that the correct name for this species is Armillaria socialis (in my opinion, reasonably). But Mycobank and Spec.fungorum give these two as different species (last year they called the A. tabescens the correct name, I guess that is where the synonymy here came from). Should we make A. socialis the correct name (possibly leaving tabescens as valid too)?

Number of users interested in this name: 3